The overall objective of the proposed research is a better understanding of the function of brain biogenic amine neurons, their differential modes of transmitter storage and release, and the interaction with these neurons of psychoactive drugs such as antipsychotics, antidepressants, and psychotogenic stimulants. Some examples of proposed research are: 1) Further examination of our observation of stereospecific amphetamine binding to an amphetamine receptor on dopamine (striatal) synaptosomes where the binding site appears to be the dopamine uptake carrier. Since this finding is consistent with the stereoselectivity of amphetamine on nigrostriatal dopamine neurons, we will examine specificity of d versus 1-amphetamine on other dopamine and norepinephrine neuronal regions as well as to characterize further the observed binding. 2) In conjunction with the above we will explore biochemically and electrophysiologically our observations on the markedly differing stereoselectivity of the actions of amphetamine isomers on dopamine cells of mesolimbic bersus neostriatal dopamine neurons. 3) Further examination of our proposal that nonamphetamine psychotogenic stimulants (e.g., amfonelic acid, cocaine), unlike amphetamine, act indirectly by inhibition of dopamine uptake, thus altering a dopamine neuronal feedback mechanism controlling interchange of dopamine pools. 4) Further examination of our observation that there appears to be a link between dopamine storage granular function and dopamine neuronal presynaptic receptors controlling dopamine synthesis.